However, most of the time the user doesn't enter their city name. There was something I read about dynamic location insertion but that is only possible if you are using location extensions. I'm not using location extension because this service is a mobile service that goes far beyond the business address.
I want the name of the closest city to the user to automatically be inserted in the ad.
The only way I can thing of to do this is to setup multiple campaigns, each one with a location target for a city and then put the city name in the ad text.
However I am concerned that location targeting isn't perfect AND there may be locations in the county that "fall through the cracks" not being within one of my city campaign location targets.
If I have a campaign for the entire county and a campaign for a city within that county, how do I insure only the ad from the city campaign is targeted if the user's location matches both campaign location targets? Make sure the corresponding keyword bid in the City campaign is higher than the County campaign? That could be a bit of a management nightmare. Or will Google only display the ad from the campaign with the most specific target location that matches?